题干

2009年5月,航天飞机在完成对哈勃空间望远镜的维修任务后,在A点从圆形轨道Ⅰ进入椭圆轨道Ⅱ,B为轨道Ⅱ上的一点,如图所示.关于航天飞机的运动,下列说法中不正确的有(   )

A:在轨道Ⅱ上经过A的速度小于经过B的速度

B:在轨道Ⅱ上经过A的动能小于在轨道Ⅰ上经过A的动能

C:在轨道Ⅱ上运动的周期大于在轨道Ⅰ上运动的周期

D:在轨道Ⅱ上经过A的加速度小于在轨道Ⅰ上经过A的加速度

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A,C,D

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Ways to say “Happy birthday to me”

    Tomorrow is my birthday, and I'm at an age when not everyone looks forward to cakes and presents.____It always makes me feel excited to be alive and grateful for my life and my family. So I think even if your birthday is a regular old day at work or home, there are some easy ways to raise it to the special occasion.

    Give a gift to someone else.____While everyone loves to open a birthday present, there is a lot of joy and goodness to be gained from being generous with others. Making a birthday donation(捐赠)to a charity that means something to you.____.

    Try something new. Today is new to us. Why not enjoy the newness of the moment? Dip your tones into some new waters, sign up for an adult education class, go for a new-to-you park or plan a new trip.____

    ____Whether or not you have the opportunity to share a meal, outing or party with friends and family, please take time on your birthday to connect with people who are important to your life. if you use social media like phones, you are likely filled with well-wishes from loved ones. Use these as a jumping-off point to start new conversations and reconnect with people who lift your spirits and support in your journey towards being your best self.

A. Connect with people who matter to you.

B. Freshen up yourself with countless opportunities.

C. It's better to give than to receive

D. This year my birthday is on a Saturday.

E. I love my birthday, though.

F. Download an app to learn a new language is also a good choice.

G. One choice is to donate a dollar amount to match your age.